docs: def quoted_string_literal(txt):
      """
      SOQL requires single quotes to be escaped.
      http://www.salesforce.com/us/developer/docs/soql_sosl/Content/sforce_api_calls_soql_select_quotedstringescapes.htm
      """
      try:
          return "'%s'" % (txt.replace("\\", "\\\\").replace("'", "\\'"),)
      except TypeError:
          raise NotSupportedError("Cannot quote %r objects: %r" % (type(txt), txt))